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O Ohtani

Publications and source records attributed to O Ohtani.

67 records · Page 4Linked to original sources
PubMed1982

Differences in the behavior of SH-protease inhibitor of rat epidermis on cathepsins B and H.

1. SH-protease inhibitor was purified from newborn rat epidermis and its activity against cathepsins B and H compared using alpha-N-benzoyl-DL-arginine-2-napthylamide as a substrate. 2. Preincubation of the inhibitor with the enzymes at 37 degrees C resulted in increased inhibitor activity for cathepsin B but not for cathepsin H: pH 7.0 was more effective than the lower pH for the increase. 3. The inhibition was noncompetitive regardless of the preincubation conditions and the inhibition was greater for cathepsin H than cathepsin B. 4. These findings suggest that there is an SH-protease inhibitor of newborn rat epidermis which has different biological behavior against cathepsins B and H.

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PubMed1982

Biochemical properties of thiol proteinase inhibitor purified from psoriatic scales.

Epidermal thiol proteinase inhibitor (EPI) was extracted from normal and psoriatic cornified cells with 10 mM Tris-HCl, pH 8.0, and purified by papain-Sepharose affinity chromatography and gel filtration. Both EPIs showed a single band and the same mobility in gel electrophoresis with and without sodium dodecyl sulfate. Their immunological identity also was seen by agar diffusion. The inhibitor activity of EPIs to papain and rat liver lysosomal enzymes which caused a local inflammatory reaction after intradermal injection was determined on alpha-N-benzoyl-DL-arginine-2-naphthylamide and azocasein. Their activities to papain were the same at pH 8.0, but EPI of psoriasis showed only 50% of the activity of normal cells at pH 5.0 and 6.0. EPI of normal cells was heat stable, while that of psoriasis was reduced in activity after heating at 90 degrees C. Inhibitor activity of EPI from psoriatic cells toward the lysosomal enzymes, cathepsin B and/or cathepsin H and cathepsin L, was also inferior to EPI from normal cells at all pHs studied. We suggest the possibility that the inflammatory response associated with psoriasis seems in part to result from epidermal cells producing a less effective EPI, which may be a natural anti-inflammatory substance.

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PubMed1982

The microvasculature of the rat vas deferens: a scanning electron and light microscopic study.

The microvasculature of rat vas deferens was studied by scanning electron microscopy of corrosion vascular casts and intact tissues. The larger arterial supply and venous drainage vessels were also studied by light microscopy of silicone rubber-injected and cleared tissue. The distal two thirds of the vas deferens has four vascular layers: an adventitial layer, a vascular network in the muscle layers, a sinusoidal network in the lamina propria and a subepithelial capillary network. The proximal third of the vas deferens lacks the sinusoidal network. This sinusoidal network in the lamina propria may be an erectile tissue which could facilitate the transport of spermatozoa along the vas deferens on ejaculation. The deferential veins commencing at the cauda epididymis drain the vas deferens, except for its distal end which is drained by the veins connected with those of the dorsolateral prostate and seminal vesicle.

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PubMed1980

Renal microcirculation of the bullfrog, Rana catesbeiana. A scanning electron microscope study of vascular casts.

The microcirculation of the bullfrog kidney was studied by scanning electron microscopy of the corrosion casts. The bullfrog kidney derives its blood supply from a dual origin: one is from the posterior half of the body via the renal portal veins and the dorso-lumbar veins, the other is from the urogenital arteries. The renal portal veins are linked with the hepatic portal system through the anterior abdominal vein which might serve as a transport route of the potentially renal portal blood to the kidney. The glomerulus consists of several lobules of anastomosing capillaries which are intercalated between the afferent and efferent arteriole. The efferent arteriole of the glomerulus runs some distance ventrad without branching to join the peritubular sinusoidal capillaries near the ventral surface of the kidney. Usually each glomerulus has a single efferent arteriole, but double efferent arterioles may rarely occur. Near the medial border of the kidney the glomeruli are small, and laterally they become progressively larger.

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PubMed1980

Microvasculature of the rat lung as revealed by scanning electron microscopy of corrosion casts.

The pulmonary microvasculature of rats was studied by injection replicas prepared from Mercox. This medium enabled us to easily obtain consistant, stable and complete injected replicas of the pulmonary vasculature. The pulmonary arteries repeated branching as far as the pulmonary arterioles, and then formed rich, basket-like anastomosing capillary networks in the alveolar walls. These capillary networks were collected into the tributaries of the pulmonary veins. The walls of the pulmonary veins, down to small branches of approximately 100 micrometers in diameter, were surrounded by one to three layers of circular or obliquely oriented capillaries with longitudinal connections. The pulmonary artery had only a single layer of capillary network in the adventitia. The vasa vasorum of the pulmonary vessels were collected into venules. They were confluent to the bronchial veins outside the lung and into the tributaries of the pulmonary veins within the lung. The bronchial tree was supplied by the bronchial arteries which form the coarse capillary plexus extending as far as the terminal bronchioles. The trachea and the proximal parts of the bronchi drained into the bronchial veins connected with the superior vena cava. The distal parts of the bronchial tree drained into the tributaries of the pulmonary veins, or adjacent capillary networks in and around the alveolar walls.

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PubMedDate not supplied

Comparative analysis of insulo-acinar portal system in rats, guinea pigs, and dogs.

The insulo-acinar portal system in the rat, guinea pig, and dog was comparatively analyzed using corrosion casting method in scanning electron microscopy and confocal laser scanning microscopy. In all animals examined, there were three types of arterioles according to their destination: 1) the arteriole which supplied the capillary glomerulus of the islet, 2) the arterioles which directly branched out into capillaries around the acini, and 3) the arterioles which supplied the duct system. In the rat, the afferent vessel usually ended in the cortical layer of the islet and its main branches ran along this layer before giving secondary capillary branches into the deeper regions, while in the dog and guinea pig, the region where the afferent arterioles branched out into secondary capillary branches varied among individual islets. There were three types of efferent vessels of the islet: 1) the insulo-acinar portal vessels that radiated from the islet to join the capillary network in the exocrine pancreas, 2) the emissary venules of the islet, leading directly into the systemic circulation, and 3) the insulo-ductal portal vessels which drained into the peri-ductal capillary network. In the rat and guinea pig, the intralobular islets possessed both the insulo-acinar portal vessels and the emissary venules, while the interlobular islets possessed emissary venules with occasionally occurring insulo-acinar portal vessels. In the dog, most of the islets were located within the lobule and possessed preferentially the insulo-acinar portal vessels. In this animal, the lobule was supplied by several microvascular units, in the center of which was located the capillary glomerulus of the islet. The peri-insular zone of the unit was mainly supplied by the insulo-acinar portal vessels, while the periphery, the tele-insular zone, was directly supplied by arterioles as well. The venules originated at the periphery of the unit. The islet in the dog had virtually no emissary venules. Confocal laser scanning microscopy of the rat islets showed that B cells occupied the core of all islets. The microvascular architecture within the rat islet appeared to be organized as to drain blood from the A and D cell area to the B cell area of the islet.

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PubMedDate not supplied

Localization of antigenic determinants recognized by a monoclonal antibody in rat epididymal spermatozoa, with particular reference to sperm maturation.

This study localized antigenic determinants recognized by a mouse anti-human sperm monoclonal antibody TüS10 immunocytochemically and immunoelectron microscopically in the rat sperm recovered from the caput and cauda epididymidis. Immunocytochemistry showed that the antibody bound specifically to the plasma membrane overlying the principal piece of membrane-intact sperm from the caput and cauda epididymidis. Demembranation by Triton X-100 significantly decreased the affinity of the monoclonal antibody TüS10 to the caput sperm but did not obviously change that to the cauda sperm. Immunoelectron microscopy with biotin-streptavidin peroxidase complex pre-embedding method confirmed the localization of the antigenic determinants over the cell surface of the principal piece of the membrane-intact spermatozoa from the caput and cauda epididymidis. The demembranated sperm from the caput epididymidis showed no intracellular labelling, while those from the cauda displayed labelling on their external surface of the fibrous sheath. Using monoclonal antibody TüS10 as a probe, we detected different distribution patterns of the antigenic determinants between the spermatozoa in the caput and cauda epididymidis. These results suggest that spermatozoa mature with immunologically detectable changes in the fibrous sheath during their epididymal transit.

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